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© John Wiley & Sons Ltd, The Geologists’ Association & The Geological Society of London, Geology Today, Vol. 31, No. 1, January–February 2015

FeatureFake it till you make it—the uncanny art of forging amber

Mats E. Eriksson1 & George O. Poinar, Jr.2

1Department of Geology,

Lund University, Sölvegatan

12, SE-223 62 Lund,

Sweden

[email protected] 2Department of Integrative

Biology, Oregon State

University, Corvallis, OR

97331, USA

poinarg@science.

oregonstate.edu

Amber has fascinated people since the Stone Age and as one of the best means of preservation of fossil organisms, it tickles our senses. The animals that are sometimes trapped in amber, like frozen moments of long-lost ecosystems, can be so incredibly well preserved that they look modern—which, in some cases, has proven to be just the case. Because fossil-bearing amber not only has a significant scientific value but is also a desired commodity on the open market, fake amber has unfortunately been around for centuries.

Anyone who has, by mistake, sat on wood seeping with resin knows how annoyingly sticky it is. Yet it is precisely this attribute that is its great advantage to scientists, as it works exceptionally well as a death trap for organisms. Its geological equivalent, amber, preserves some magnificent fossils for detailed studies. Just like the sedimentary rock record itself, however, it is only a fraction of all amber which actually con-tains remains of organisms, usually referred to as inclusions.

The organisms that are trapped like time capsules in amber are often exceptionally well preserved and have therefore contributed with vast amounts of unique knowledge of the biodiversity in ancient terres-trial ecosystems and the biology of individual extinct species. By far the most common fossils are members of the insect order Diptera, particularly common in Baltic amber. But there is a whole array of organ-isms that have been recorded in amber, ranging from bacteria and invertebrates—such as nematodes, bee-tles, mites, scorpions, and spiders—via plant remains to vertebrates in the shape of small amphibians and reptiles (Fig. 1). Even the remains of larger animals, such as fur and feathers from mammals, birds and dinosaurs, have been identified in this substance.

In addition to their fascinating diversity, fossils preserved in amber may show animal interactions, which in general is exceedingly rare in the traditional fossil record. Like frozen moments of ancient worlds the animals are sometimes preserved in life positions, Pompeii-style. These poses can be anything from par-asites exploiting their hosts, spiders feasting on insects

caught in their webs, worker ants carrying food and construction materials, bees with outstretched wings carrying pollen, and flies suffering from coitus inter-ruptus of the deadly kind.

In certain, particularly well-preserved, amber fos-sils, minute and delicate soft tissue structures have been identified, such as microscopic muscle fibres and tracheae—or the breathing apparatuses of insects. Sometimes, even cells with nuclei and mitochondria have been recorded in several million-year-old fossils. This also reveals the amazing quality of resin as a fixation agent, and its ability for natural mummifica-tion.

Collectively, it is evident that amber fossils hide

Fig. 1. An excellently preserved Sphaerodactylus gecko in Dominican amber. The nearly complete lizard measures 4.3 cm in length and is one of relatively few known authentic vertebrates in amber. (Image: George Poinar).

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amazing secrets of ancient worlds ready to be deci-phered by eager researchers, and that they possess a very high scientific value. Unfortunately, however, fossil-bearing amber is also of substantial commercial value—inclusions of small vertebrates for instance can easily cost £6000 or considerably more if they are authentic—which has paved the way for an ex-tensive market of fakes.

Processed and faked amber

As soon as something becomes desirable and is there-fore considered valuable, clones and replicas appear on the market. There is perhaps nothing wrong with this per se, so long as such items are not marketed as the real deal. Who has not bought cheaper replicas of various designer products from a world famous Swedish furniture company, just to take one exam-ple? However, when it comes to amber, man-made pieces are often promoted as authentic, and then it becomes just forgery, plain and simple.

When studying the literature it almost gives you the impression that all amber that is sold commer-cially at different market places around the world is fake. Of course the situation is not really that bad, but fake amber is found basically all over the world form-ing the basis of a large and shady industry. Moreover, the ‘tradition’ of forging amber is indeed old and fakes with enclosed fossils go back at least 600 years, if not further. The reason for this is probably not only a consequence of amber being in high demand, but also that it is pretty easy to fake.

Amber fakes can be subdivided into two catego-ries, of which the first one actually encompasses true amber and is therefore borderline fake. It should prob-ably rather be regarded as some sort of modification or ‘improvement’. One such example is ‘ambroid’, which is relatively natural looking amber that is fab-ricated by pressing together smaller pieces of amber under heat (Fig. 2). By doing so, worthless pieces can be recycled and remodelled into a bigger amber chunk that can subsequently be processed further, for

example into beads for making jewellery.Another common feature is the production of

sparkling reflective discs, colloquially known as ‘sun spangles’ (Fig. 3). These objects appear like golden discs floating in the amber matrix. This is also a tell-tale sign that the amber has been processed; the sun spangles are former trapped air bubbles that have expanded and cracked into disc-like fractures, after heating the amber in dry sand. Yet another treatment method, which also has a long tradition, is to gradu-ally and gently heat the amber in a bath of oil or fat. By doing so, some of the trapped air bubbles close to the surface become filled and the end result is clearer, more transparent amber.

The second category, however, has nothing to do with amber but consists of some sort of substitute material that simply looks like amber! In this category we can also include natural copal—younger and not yet completely polymerized, or fossilized, resin—of-ten falsely promoted as amber, which is quite com-mon (Fig. 2). Other substitute materials have varied over the years and include, for example, rock, glass, bakelite and bone. Today it is probably most common to use some sort of synthetic polyester resins, but also copal that has been processed in various ways.

Bogus fossils in faked and real amber

One common technique of making fake amber with fossil inclusions is to embed an organism in synthetic resin or melted copal (Figs 4–8). Authentic amber cannot be melted properly for the purpose, as it black-ens and usually catches fire in the process. If copal is used, it is first usually ground, mixed with some solvent (such as turpentine) and then melted. During this process, the paste can also be dyed to a desired tint. Then it is possible to just to pour the mixture into a mould, as if you were making cupcakes, and add an organism of choice.

Fig. 2. Amber-esque copal from east Africa and, to the right, a piece of processed ambroid. (Images: Mats E. Eriksson).

Fig. 3. Amber-like plastic beads with typical ‘sun spangles’ which are common in processed amber. (Image: George Poinar).

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Copal fakes can be a little tricky to reveal, par-ticularly since there is copal that naturally has au-thentic organism inclusions (which also makes it scientifically interesting by itself). Even though copal has slightly different chemical properties and a lower melting point, it can be similar in appearance to gen-uine amber. As a testament to this are quite a number of examples of amber insects that have been described ‘in good faith’ from museum collections, that were purchased as amber but upon re-examination and chemical analyses turned out to be copal (albeit not forged).

Sometimes genuine amber is used for making fakes. In order to conceal external signs of tamper-ing, a piece of amber is first split open along a natural fissure. A small niche is then carved or drilled into one of the pieces, filled with synthetic resin and some (hopefully already) dead animal. Thereafter the two pieces are carefully fitted together and all traces of

manipulation are taken care of. This type of counter-feit amber, which also has the oldest history, can be highly refined if they are carefully made. Moreover, because they are made out of genuine amber, various chemical tests of the surface will give false signals that it truly is genuine.

A relatively new technique is to embed an animal in a plastic resin layer and then attach that layer to a piece of genuine amber (Fig. 9). With this combina-tion, the animal is never in the amber, it just appears to be. A person testing the piece would normally take a sample from the undersurface so as not to mar the view of the animal. That portion of the piece would test positive for amber.

The fake tales of a latrine fly

One should remember that the vast majority of the forged amber has not been made with the intention of duping science and scientists, but for one bright and shiny reason: profit! Even if this is the intention, and despite the fact that it is usually quite easy for experts to detect forgeries, there are actual cases in which amber forgeries have resulted in quite unfortunate scientific consequences.

One of the most famous such cases is the so-called Piltdown Fly (Fig. 10). The name obviously flirts with the Piltdown Man, the world’s most famous case of palaeontological fraud in which the jaw bone of an orang-utan was merged with parts of a human cra-nium in order to dupe the scientific community of the existence of a new human species. Again, the differ-ence in the case of the fly was that the underlying intention was not a conscious scientific hoax.

It was a piece of 38-million-year-old Baltic amber

Fig. 4. A relatively authentic looking amber fake, 3 cm in diameter, with a modern spider encased in melted Congo copal. (Image: George Poinar).

Fig. 5. A big spider, the body alone measures 3 cm in length, encased in Kauri Gum—a kind of copal from New Zealand. The huntsman spider (Delena cancerides) is a harmless celebrity, starring in the movies Spiderman and Arachnophobia. (Image: George Poinar).

Fig. 6. A pendant, approximately 1.5 cm in diameter, from Morocco with an ant in amber-like plastic. (Image: George Poinar).

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with an inclusion of a very well preserved fly that was stored in the collections of the Natural History Muse-um (NHM) in London. The piece originally came from the German collector and insect researcher Herrmann Loew, and was bought by the museum in 1922. By the mid-1960s a certain Willi Hennig (1913–1976) got wind of the specimen and studied it carefully. Hennig was a very well-known biologist and is one of the most influential systematists of modern time (for instance he is the father of phylogenetic systematics, or ‘cladistics’). He, moreover, was specialized in dip-terans and had published quite a great deal on fossil flies embedded in amber. This background also gave scientific weight behind the results that were to be revealed, which is perhaps a reason why the results were not scrutinized.

Hennig immediately realized that it was a piece

of Baltic amber, based on the colour, texture and the trapped microscopic irregularities and impurities. Being well aware of fakes in copal, he considered the fact that it could be a fake but he could not see any signs pointing in that direction. Since the fly was in-distinguishable from the now living latrine fly, Fannia scalaris, Hennig published a paper that among other things dealt with evolutionary stasis of insects, i.e. how insect species could remain unaltered for a very

Box 1: Amber—fossilized resin

Formation: Resin can be regarded as the artillery of the trees, produced as a defence mechanism towards insect attacks and disease. Usually resin is broken down quite rapidly due to natural physical, chemical and biological processes. However, there are certain types of resin that are more resistant than others and if such resin ends up on the ground and becomes a part of sediment, the prerequisites for amber formation are met. When the resin-rich sediment is overlain by other sediments, pressure and temperature increase and the resin starts to polymerize. First it transforms into copal, or subfossil amber, and through additional heat and pressure over long time, into amber.

Hardness: 2–2.5 on Mohs scale of mineral hardness. For comparison, quartz has a hardness of 7 and diamond tops the scale with a hardness of 10.

Appearance: Commonly reddish-yellowish, honey-coloured, but amber ranges from red, brown, green, to almost black. The most sought after and valuable is the blue variety from the Dominican Republic. Amber also varies from clear, via cloudy to completely opaque. The latter is usually a consequence of numerous tiny trapped air bubbles.

Density: Approximately 1.08. This is just above fresh water and which means that it will float in salt water. This is also the reason why amber can be transported long distances in the oceans and wash up on beaches during storms.

Fire and oxidation: Amber oxidizes gradually and may be destroyed with time if exposed to heat or air, which is why archaeological finds and old museum specimens may appear degraded. The fact that amber burns and releases a pleasant smell has proven advantageous for revealing fakes.

Age: From 320 million years old (the Carboniferous Period) to perhaps a couple of hundred thousand years old (the precise age at which copal turns into amber is not known). The oldest amber with arthropod inclusions is approximately 230 million years old (the Triassic Period).

Some famous localities: Lebanon, Mexico, Russia (west of Kaliningrad in particular), Dominican Republic (Dominican amber), the Baltic coasts (Baltic amber).

Static electricity: The fact that amber can be electrostatically charged has been known since ancient Greece. The words electricity and electron derive from the old Greek word for amber.

Use: A sought after gemstone and used as adornment and for jewellery for at least 13 000 years. It has also been used as a trading commodity, and as an ingredient in incense and perfume. Similar to many fossils and minerals, throughout history it has also been attributed with healing and magical properties.

Fig. 7. A mosquito inserted in amber-coloured plastic. (Image: George Poinar).

Fig. 8. Unusually ‘well-preserved’ cockroaches, of which the bigger one measures 4 cm in length. The specimens are, however, modern ones that have been inserted in amber-like plastic. (Image: George Poinar).

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(a) (b)

long time. As a forecast of what was to come, Hen-nig’s article was published (surely by coincidence) on April Fool’s Day, 1 April 1966.

Although there were signs in the fly that perhaps should have been warning bells, such as its bright red eyes, the forgery must have been very well made since it eluded the sharp and critical eyes of Hennig. It was not until almost thirty years later, in 1993, that the fake was revealed, simply by accident. Amber re-searcher Andrew J. Ross was studying the collections at the NHM in London and while the Fannia scalaris piece from Hennig was under scrutiny, the heat from his microscope lamp made it crack open in an un-natural fashion. This revealed that a small niche had been carved out of authentic Baltic amber and filled with synthetic resin and the fly.

The fact that it was a latrine fly was probably coincidental, and what was available on the win-dow pane at the time of its manufacture. These flies

were quite common in rural areas in the nineteenth century—whereas they are much less common to-day due to improved hygiene and garbage disposal management.

The art of revealing the forgeries

Just as in art forgeries there is a broad spectrum represented among amber fakes, from clumsy pieces that are easily spotted even for the inexperienced eye, to those that can deceive even the most dedicated amber expert. In order to be fully convinced about the authenticity, sophisticated analytical techniques are required, or a combination of different tests. For instance, mass spectroscopy, gas chromatography, UV-light (Fig. 9), and infrared spectrometry can be employed in order to obtain very precise chemical and optical properties of the material and thereby sort the fakes from the genuine pieces. As a drawback, these techniques may be complicated, costly, and usually require advanced instrumentation. There are, howev-er, some simple household tricks that are often quite efficient; simply use your own senses combined with the particular properties of amber.

A careful visual inspection can provide some hints, since certain types of amber have a very character-istic colour or surface structure. However, it should be remembered that the colour of amber can vary quite substantially, and even from one and the same area, and synthetic resin can be dyed to achieve the ‘correct’ hue.

Genuine amber usually contains quite a lot of im-purities such as microscopic hairs and the remains of insects and plants, but also flaws and irregulari-ties such as trapped air bubbles, swirls and fractures. Some forgers have started to sprinkle their pieces with dirt and dust in order to achieve a more authentic appearance. However, those are usually quite easy

Fig. 9. a. Dorsal view of a real frog that appears to be entombed in amber. b. Under ultraviolet light, the fluorescence shows that the frog had been placed in a plastic layer (clear light blue region) attached to a piece of amber (yellowish region). Examining the piece from the top (as in a.) indicates that the frog is in a solid piece of amber (Images: photo courtesy of International Gemological Institute [IGI]).

Fig. 10. The ‘Piltdown Fly’ that fooled Willi Hennig turned out to be a very well made forgery from the nineteenth century with a latrine fly, Fannia sclaris, inserted in Baltic amber. (Image: Natural History Museum, London).

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to tell apart from real impurities. Of course there is also genuine amber that is very clear and beautiful, for example from the Dominican Republic, but flaws and impurities are nonetheless usually a sign in the right direction.

If amber is rubbed vigorously against fur or a piece of coarse cloth, static electricity is formed and if you smell the piece just after this treatment, there is a mild scent of resin. Some plastic materials can of course be charged with static electricity, which is good to know if a dealer is trying to convince you that this is the real deal, but the smell is difficult to mimic.

Your own teeth can actually form quite efficient tools for recognising amber and there are amber col-lectors that put their beach findings in their mouths or carefully tap the pieces against their teeth in or-der to discriminate amber from other materials. Glass and rocks have a different hardness and feel different against the teeth. Some plastic materials have a simi-lar feeling, but this is usually not a big problem, at least on beaches. Because it is so soft, amber is also easily scratched with a pin, unlike many substitute materials.

If ether or alcohol is dropped on the surface and al-lowed to vaporize, copal for instance will get a sticky surface whereas amber will not be affected. Hence this is a good test for copal but there are synthetic substitute materials that react differently to this treat-ment. Alcohol and other solvents can also clean off surface treatments and colour coatings, and in that way reveal a fake.

Another common and easy test is to mix a concen-trated salt water solution and take advantage of the low specific gravity of amber. In such a liquid, amber and copal will float whereas many substitute materi-als, including many plastic materials, will sink.

Amber burns and in the process releases a mild and nice smell similar to pine resin or incense. This

is in sharp contrast to substitute materials like rock and glass that do not burn, different plastic materials that do burn but release a characteristic pungent and sticky smell, or bone that smells like burning hair. So, an easy test is simply to put a heated needle to the material and sniff the smoke. Again, also this prop-erty is known by dealers in amber rich areas and is sometimes used to prove to unsuspecting tourists that what they are selling is the real deal. An amber fake can be smeared with a little pine sap and if then held over a burning match, the smell is as it should be.

Bugs on display?

When it comes to amber fossils the tests outlined above can be complemented by visual signs that should cause suspicion. Are the inclusions at all au-thentic, or are they (also) made of plastic? Does the animal belong in the resin-producing environment (Fig. 11)? Sometimes frauds made of Kauri Gum, a copal from New Zealand, are found with encased or-ganisms that are not, and have never been, present in New Zealand. One should also consider if it is a com-mon, modern-day insect species? If so, an entomolo-gist can usually reveal such fakes relatively easily.

How big are the inclusions? Amber fossils are com-monly tiny and thus if they are in the size range of a couple of centimetres and upwards, it is suspicious. Bigger and stronger organisms can usually break free from the sticky resin with greater ease. Moreover, since vertebrates, such as small lizards and frogs, are exceptionally rare in amber, one should be extra alert for such inclusions and be aware of the fact that al-most all specimens on the open market are fraudulent (Figs 12–13)

What about the mode of preservation? Genuine amber fossils are usually somewhat dehydrated, and can be slightly flattened and deformed. There are ob-viously exceptions; those that are sometimes found

Fig. 11. An exceptionally well-preserved trilobite (measuring 8 cm in length) in Baltic amber. But is it real? Disregarding the fact that both the trilobite and the amber are made of plastic, the trilobite genus Paradoxides lived during the Cambrian Period, that is a couple of hundred million years before there were any resin-producing land plants, and in marine environments. The beautiful forgery was kindly produced for the senior author by 10 Tons Studios, Copenhagen. (Image: Esben Horn).

Fig. 12. A 9 cm long frog, Litoria raniformis, embedded in Kauri Gum. The species is indigenous to Australia and introduced to New Zealand. It is nowadays rare and on the list of endangered species. (Image: George Poinar).

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for example in Dominican amber are often wonder-fully and three-dimensionally preserved, which obvi-ously makes them easier to fake.

In Baltic amber there is usually a thin milky layer between the inclusion and the surrounding amber matrix. This is very difficult to fake (and has not yet been reported). By contrast, in fakes it is not uncom-mon to see thin layers of air trapped between the inclusion and the synthetic amber matrix that is not present in genuine amber pieces (Fig. 14).

Does it appear as if somebody laid out a perfect organism in resin, with all extremities nicely spread apart? Well, then someone probably did and it is

almost certainly a fake (Fig. 14). Animals that are trapped in resin often have a distorted appearance, with bent legs and wings.

See no evil, hear no evil…

Unfortunately the ‘art’ of making amber fakes is con-stantly evolving and improving and as long as there is a demand for amber there will be also be a supply of counterfeits. It is at least reassuring to know that there are a number of tricks that can be used to re-veal the fakes. Because some of these techniques are slightly destructive, however, it is probably wise to use some caution before testing the authenticity of your relatives’ favourite piece of jewellery. Another cautionary tale is this; you might want to ask yourself if you really want to know if your prized possession is real or not? As you may not approve of the result, sometimes ignorance is bliss.

Acknowledgements

Sincere thanks to Esben Horn and the 10 Tons Studios for making the trilobite amber fake and providing images of it.

Suggestions for further reading

Eriksson, M.E. 2014. Förhistorisk kåda med unika egenskaper: Bärnsten—favorit hos forskare och förfalskare. Allt om Vetenskap, v.7, pp.46–53. [In Swedish; a modified and translated version of this paper forms the basis for the present article.]

Grimaldi, D.A. 1996. Amber—Window to the Past. Harry M. Abrams Inc., Washington, DC.

Grimaldi, D.A., Shedrinsky, A., Ross, A. & Baer, N.S. 1994. Forgeries of fossils in ‘amber’: history, iden-tification and case studies. Curator, v.37, pp.251–274.

Palmer, D. 1993. Fatal flaw fingers fake fossil fly. New Scientist, v.13, November, pp.4–5.

Poinar, G.O. 1982. Amber—true or false? Gems and minerals, v.534, pp.80–84.

Poinar, G. & Poinar, R. 1994. The Quest for Life in Amber. Perseus Publishing. Cambridge, Massachu-setts. 219 p.

Ross, A.J. 1993. The ‘Piltdown Fly’. Palaeontology Newsletter, v.20, p.16.

Ross, A.J. 1997. Insects in amber. Geology Today, January–February 1997, pp.24–28.

Fig. 14. An approximately 4 cm long, sagrine beetle, encased in plastic. Note how nicely stretched out its legs are, as if the animal is on display (which in a way it is!). A thin layer of air can also be seen on the hind part of the beetle. (Image: George Poinar).

Fig. 13. An unusually large fake amber piece with a gecko in Kauri Gum. The lizard measures approximately 15 cm in stretched out position and this size alone is a cause for serious suspicion. The ‘crazed’ surface pattern might look odd but it is actually strongly reminiscent of that of many oxidized real pieces of amber and copal from older museum collections. (Image: George Poinar).

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